The invention discloses a miniaturizedlinear polarization, dual polarization, circular polarization and triple polarization 5G antenna, which is characterized in that two orthogonal capacitive slits in transverse and longitudinal directions are formed in a Mushroom structure in a traditional metamaterial to form a novel electromagnetic metamaterial resonator structure, namely an annular resonator,so that a negative first-order resonance mode is excited; impedance, field distribution and radiation characteristics similar to those of a traditional positive first-order mode are achieved while miniaturization design is achieved. Through proper coupling feed excitation or other coaxial back feed and differential feed modes, miniature linear polarization, dual polarization, circular polarization and tri-polarization antenna design is realized, open-circuit microstrip line branches are connected in series on a floor back coupling feed line, and a new resonance mode is introduced, so that double resonance points appear in a band, the antenna bandwidth is effectively expanded, and the antenna performance is improved. And the bandwidth requirement of a 5G new frequency band is met. In addition, a standard system metal screw is adopted for supporting and a small number of dielectric substrates are adopted, so that dielectric loss is reduced as much as possible, and high radiation efficiency is kept.